<div class="widget widget_search">
    <form class="navbar-form" action="<?php $this->options->siteUrl(); ?>" method="post">
        <div class="input-group">
            <input type="text" name="s" class="form-control" size="35" placeholder="请输入关键字"
                maxlength="15" autocomplete="off"/>
            <span class="input-group-btn">
                <button class="btn btn-default btn-search" name="search" type="submit">搜索</button>
            </span>
        </div>
    </form>
</div>